/* Base Variables & Reset */
:root {
  /* Colors - Aviation Theme */
  --color-primary: #1e3a5f; /* Deep Navy */
  --color-primary-light: #2b5082;
  --color-primary-dark: #12243d;
  --color-secondary: #4a5d73; /* Steel Grey */
  --color-accent: #d9534f; /* Alert/Safety Orange-Red */
  --color-accent-hover: #c9302c;
  
  --color-bg: #f8f9fa; /* Off-white / light silver */
  --color-bg-alt: #ffffff;
  --color-text: #212529;
  --color-text-muted: #6c757d;
  --color-border: #dee2e6;
  
  --color-footer-bg: #111b27;
  --color-footer-text: #cbd5e1;

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;
  --space-8: 4rem;
  --space-12: 6rem;
  --space-16: 8rem;

  --border-radius: 4px;
  --border-radius-lg: 8px;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  
  /* Layout */
  --container-width: 1200px;
}

@media (prefers-reduced-motion: reduce) {
  :root {
    --transition-fast: 0s;
    --transition-normal: 0s;
  }
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  color: var(--color-primary-dark);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--space-3);
  letter-spacing: -0.02em;
}

h1 {
  font-size: 2.5rem;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
p { margin-bottom: var(--space-3); }

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover, a:focus {
  color: var(--color-accent);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

main {
  flex: 1;
}

.section {
  padding: var(--space-12) 0;
}

.section-alt {
  background-color: var(--color-bg-alt);
}

/* Header & Nav */
.site-header {
  background-color: var(--color-primary-dark);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-md);
  border-bottom: 2px solid var(--color-accent);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  color: #fff;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.logo:hover, .logo:focus {
  color: #fff;
  opacity: 0.9;
}

.nav-links {
  display: flex;
  gap: var(--space-5);
  list-style: none;
}

.nav-links a {
  color: #e2e8f0;
  font-weight: 500;
  text-transform: uppercase;
  font-size: 0.9rem;
  letter-spacing: 0.05em;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: #fff;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--color-accent);
  transform: scaleX(0);
  transition: transform var(--transition-normal);
  transform-origin: right;
}

.nav-links a:hover::after,
.nav-links a[aria-current="page"]::after {
  transform: scaleX(1);
  transform-origin: left;
}

.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  color: #fff;
  cursor: pointer;
  padding: var(--space-2);
}

.mobile-nav-toggle svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

/* Hero Section */
.hero {
  position: relative;
  background-color: var(--color-primary-dark);
  color: #fff;
  overflow: hidden;
  min-height: 60vh;
  display: flex;
  align-items: center;
}

.hero-bg {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.4;
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
}

.hero h1 {
  color: #fff;
  margin-bottom: var(--space-4);
}

.hero p.lead {
  font-size: 1.25rem;
  margin-bottom: var(--space-6);
  color: #e2e8f0;
  max-width: 600px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-size: 0.9rem;
  border-radius: var(--border-radius);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 2px solid transparent;
  text-align: center;
}

.btn-primary {
  background-color: var(--color-accent);
  color: #fff;
}

.btn-primary:hover, .btn-primary:focus {
  background-color: var(--color-accent-hover);
  color: #fff;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background-color: transparent;
  border-color: #fff;
  color: #fff;
}

.btn-outline:hover, .btn-outline:focus {
  background-color: rgba(255, 255, 255, 0.1);
  color: #fff;
}

/* Grid Layouts */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-8);
  align-items: center;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-6);
}

/* About Snippet & Features */
.image-wrapper {
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border: 4px solid #fff;
}

.image-wrapper img {
  width: 100%;
  transition: transform 3s ease;
}

.image-wrapper:hover img {
  transform: scale(1.05);
}

/* Forms */
.form-group {
  margin-bottom: var(--space-4);
}

.form-label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-1);
  color: var(--color-primary-dark);
}

.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius);
  font-family: var(--font-sans);
  font-size: 1rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  background-color: #fff;
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(30, 58, 95, 0.1);
}

textarea.form-control {
  min-height: 150px;
  resize: vertical;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Form Status Messages */
.form-status {
  padding: var(--space-3);
  border-radius: var(--border-radius);
  margin-top: var(--space-4);
  font-weight: 500;
  display: none;
}

.form-status.success {
  display: block;
  background-color: #d1e7dd;
  color: #0f5132;
  border: 1px solid #badbcc;
}

.form-status.error {
  display: block;
  background-color: #f8d7da;
  color: #842029;
  border: 1px solid #f5c2c7;
}

.form-status.warning {
  display: block;
  background-color: #fff3cd;
  color: #664d03;
  border: 1px solid #ffecb5;
}

/* Contact Info Box */
.contact-info-card {
  background-color: var(--color-primary-dark);
  color: #fff;
  padding: var(--space-6);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
}

.contact-info-card h3 {
  color: #fff;
}

.contact-info-card a {
  color: #e2e8f0;
  text-decoration: underline;
  text-decoration-color: rgba(255,255,255,0.3);
  text-underline-offset: 4px;
}

.contact-info-card a:hover {
  color: var(--color-accent);
  text-decoration-color: var(--color-accent);
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.contact-icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  fill: var(--color-accent);
}

/* Footer */
.site-footer {
  background-color: var(--color-footer-bg);
  color: var(--color-footer-text);
  padding: var(--space-8) 0 var(--space-4);
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-6);
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-col h4 {
  color: #fff;
  margin-bottom: var(--space-3);
  font-size: 1.1rem;
}

.footer-col a {
  color: var(--color-footer-text);
}

.footer-col a:hover {
  color: var(--color-accent);
}

.copyright {
  text-align: center;
  font-size: 0.875rem;
  color: rgba(255,255,255,0.5);
}

/* Responsive */
@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.75rem; }
  
  .grid-2 {
    grid-template-columns: 1fr;
    gap: var(--space-6);
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
  }
  
  .hero {
    min-height: 50vh;
  }
  
  .nav-links {
    position: absolute;
    top: 80px;
    left: 0;
    width: 100%;
    background-color: var(--color-primary-dark);
    flex-direction: column;
    gap: 0;
    box-shadow: var(--shadow-md);
    clip-path: polygon(0 0, 100% 0, 100% 0, 0 0);
    transition: clip-path var(--transition-normal);
  }
  
  .nav-links.is-open {
    clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
  }
  
  .nav-links li {
    border-bottom: 1px solid rgba(255,255,255,0.1);
  }
  
  .nav-links a {
    display: block;
    padding: var(--space-4);
  }
  
  .mobile-nav-toggle {
    display: block;
  }
}